import java.util.Scanner;
public class Zuoye6 {
    public static void main(String[] args) {
        Scanner in=new Scanner(System.in);
        System.out.println("请输入一个整数：");
        int a=in.nextInt();
        int b=2;
        for(b=2;;b++)
        {
            if(a%b==0)
            {
                System.out.println("不是质数。");
                break;
            }
            System.out.println("是质数。");
            break;
        }
    }
}
